Crown molding is a desirable design element that improves the appearance of interior spaces. Wood crown molding has been used in buildings for many years, and is traditionally installed where there is a fixed ceiling, and at the top of the wall, with the crown molding fastened to both the ceiling and the wall. The crown molding is securely attached to the wall by nailing with nails being passed through the decorative face of the molding into the wall, and, separately, into the ceiling. This installation method, however, leaves holes and marks where the nails travel through the decorative face, requiring patching to regain a smooth surface on the decorative face. Further, installing traditional crown molding where walls meet in the corners of a room is a known carpentry challenge, with precision cuts at difficult to determine angles required. The difficulty of satisfactorily installing traditional crown molding in corners is one of the reasons that installing traditional crown molding is considered one of the most difficult trim work installations.
Traditional wood crown molding is also largely stiff, and has little ability to flex over small longitudinal distances, such as less than one foot, and for small distances will remain very close to straight. However, there is flex with longer longitudinal distances, for example over eight feet. This means that when installed on an imperfect wall, the traditional wood crown will remain preferentially straight, as it is unable to flex over short distances, yet can flex a small amount (a couple inches) over longer distances such as eight feet. The result is a molding that appears straight to the eye, even if it is installed on a wall (and ceiling) with surface irregularities. Traditional wood crown molding that is installed over middle length irregularities (such as a waviness over a distance of one foot as an example) will not be able to flex and tightly follow the wave of the wall, but will remain largely straight against such middle-length waves. This may leave gaps where the molding remains straight against the wave, which gaps are conventionally filled with caulk to obscure the gap. With a properly installed traditional wood crown molding mounted on an irregular wall, the resulting appearance can be of a straight crown molding that draws the eye and deemphasizes the imperfections in the wall.
The present invention improves upon existing crown molding technologies by incorporating the ability to both install tightly and securely to a wall that is not perfectly straight and to maintain a preferentially straight crown molding face as seen in the room. This is accomplished by enabling two specific forms of flex to occur within the molding system; short-scale flex limited to an attachment portion of the molding, and a hinge-like action along the length of the attachment portion between (or incorporated within) the attachment portion and the decorative face, that allows the lower portion of the molding assembly to always achieve its desired location at the wall.
The hinge-like flex, in particular, is an improvement upon the crown molding system and method described in the inventors' recently issued U.S. Pat. No. 8,887,460, which molding is described as a simple pendulum, where the fastener, as it pierces the attachment flange, is above the center of mass of the entire molding system. In this simple pendulum system, the fastener serves as the pivot, and the molding structure as a whole will be constantly urged toward the wall, which is also the desired position of the crown molding. The invention requires the pivot to be at the fastener, and requires the molding to pivot as a whole, with no described accommodations for flex within the molding system that enables the pendulum effect in addition to the pivoting of the entire molding system.
The present invention, by moving the pivot of the simple pendulum system to within the molding structure itself, enables an improved molding system. While the short-scale and hinge-like flex actions occur, the structure of the molding is such that the decorative face of the molding is held in its desired position, with its lower portion against the wall and decorative face being held preferentially straight, similar to how traditional wood crown molding remains preferentially straight, even as the attachment portion flexes as needed when secured to an imperfect wall. The result of these improved parameters of flex, which are insulated from the decorative face, is a molding that, similar to traditional wood crown molding, remains primarily straight even as it is securely attached to a wall with irregularities from a perfect plane. Having a straight crown molding mounted to an imperfect wall is a desired design feature, as occupants within a room will have their eyes drawn to the straight crown molding, making the irregular wall less apparent.
The crown molding system and method described in the inventors' U.S. Pat. No. 8,887,460 offers improvements to the process of installing crown molding. However, certain wall irregularities would cause such crown molding system to install in an undesirable fashion. Further, the crown molding has no provisions for separable flex of the attachment portion, causing wall irregularities to be transmitted to the decorative face. This lack of separable flex of the attachment portion of the inventors' patented crown molding system is presented as a feature of the invention, since it allows the crown molding to “follow the uneven contour of the wall.” However, the result of a crown molding flexing to match the contours of a wavy wall that is designed to be straight is fundamentally different from the result of the improved invention described here.
The molding described in U.S. Pat. No. 8,887,460 also does not include a hinge-like flex such as in the present inventors' improved crown molding system. Without this hinge effect, the molding described in U.S. Pat. No. 8,887,460 would install over certain irregularities which would force the bottom edge of the molding away from the wall, even though lower edge of the decorative face would still be continually urged against the wall surface. As an example, if the wall has an irregularity which protrudes outside of the wall below the fastener but above the lower edge of the decorative face, this irregularity would force the lower edge of the decorative face away from the wall. The simple pendulum action does urge the lower edge of the decorative face towards the wall, but without a hinge-like action within the molding such as in the present invention, the molding would rest against the protuberance leaving the lower edge of the decorative face away from the wall.